On Wed, 2008-10-29 at 09:21 -0700, Brandon Lamb wrote:
Hello
Has anyone else run into a problem with dovecot pop3 and sonicwall? A week after switching to dovecot we had two local customers call and report they could no longer download emails with attachments. It turned out to be the email macro filter on the router. After the first report I thought maybe the customer had just changed something or it was a fluke, but then a day later we had the second call with the same issue. For some reason, after us switching the sonicwall's email macro filter was catching any attachments as a threat.
I couldnt see how changing pop3 servers could affect that, but I guess anything is possible. I just emailed sonicwall and am waiting for a response from them now as well. Hopefully maybe someone has heard of this before. Unfortunately, I dont know if this was pure coincidence, or if both customers happened to have updated their sonicwall software, or maybe it autoupdates, I have no information on it.Of course to them it looks like we broke it. We just had them both turn this rule off for now.
I've no idea, but perhaps sonicwall only looks at IP packets instead of following entire TCP streams and perhaps Dovecot is sending larger IP packets (or alternatively smaller/differently) than your previous POP3 server? Just a guess.